Definition. The time series of model-interpolated 5-delta call implied volatility for the IBIT ETF, broken out by tenor.

Technical. Each data point represents the IV at target delta 5, obtained via interpolation across delta and maturity onto standard tenors. IBIT options follow US equity market hours (9:30 AM to 4:00 PM ET, Mon to Fri), so data appears flat outside trading sessions and on weekends and holidays.